Process of converting quicklime into powdered hydrated lime.



10.773,030. y PATENTED00T.2.5,1904:.4

J. RBANEY. JB. PRooHss'oP CONVERTING QUIGKLIMB INT0 PowDBRED HYDRATED LIME.

APPLICATION FILED MAR. 16, 1904.

Patented October 25, 1904.

PATE-'NT OFFICE.

.JAMES REANEY, JR., oF

SHERWOOD, MARYLAND.

PROCESS4 O F CNVERTING QUlCKLlME INTO POWDERED HYDRATED LIME.

SPECIFICATION forming part of Letters Patent No. 773,030, dated October 25, 19051. Applicaticil led March 16, 1904. Serial No. 198,383. (No specimens.) 4

To a/ZZ whom, t may concern:

Be' it known that I, JAMES REANEY, J r. a citi` zen of the United States, residing at Sherwood, in the county of Baltimore and State of Maryland, have invented certain new and useful. Improvements in Processes of Convertingl Quicklime into Powdered Hydrated Lime, of Y which the following is a specification.

This invention relates to an improved process for converting quicklime into powdered hydrated lime and at the same time removingV from the hydrated lime any impurities, such l as unburned or overburned particles or stone. In carrying out the'process an apparatus such as illustrated in the'accompanying drawing is preferably employed, though other forms of apparatus may be used.

. The form and construction of the apparatus illustrated is made the subject of a separate application executed and filed by me simultaneously with the present application.

Briefly described, the apparatus comprises an outer housing or receptacle constructed so as to exclude air and inclosing a plurality of revoluble cylinders D and E, one within the other, with a revoluble screen f interposed between said cylinders. Theouter cylinder is imperforate, while the inner cylinder is provided with perforations, and the cylinders and. screen are inclined at different angles, so that the passage of the lime through the inner cylinder will be slower than that through the screen and outer cylinder. A steam-pipe f2, having a series oi' perforations f3, extends through the inner cylinder E, and steam is supplied. to the interior of the said cylinder through said pipe. Acharging-chute G is provided which communicates with the inner cylinder, and this-chute has a gate g, which is pivoted so as to normally keep the chute closed and confine the steam and heat within the cylinder and practically exclude the air during the process. A Water-tank /L vis pro vided with a valve which is connected with the gate g, so thatv when the latter isv opened by the passage of lime into` the inner cylinder the valve will beoperated to permit the escape of water onto the lime in the said inner cylinder. The tank is designed to contain a quantity of water a little less than is suliicient to convert a given quantity of quicklime into a perfect hydrate. The quicklime is then weighed on a scale device, (indicated at L on the drawing,) so that the proper proportions of lime with respect to the quantity of water in the tank will be mixed in the inner cylinder. The predetermined quantity of water is sprayed on the mass in the inner cylinder l while the mass is tumbled, and the dampened -mass then commingles, begins to heat, swell,

and slake, and forms some steam, which lat' ter, together with the steam supplied by the pipe f2, completes the hydration, and the liner particles sift through onto the screen f, where Athey are further broken and sifted and deposited onto the outer cylinder D.

It is desirable that both water and steam be employed to effect the com plete hydration, for the reason that if water alone were used a relatively greater quantity would have to be used, and it would be liable to pass through the perforated cylinder and also through the screen .f and into the outer cylinder, and thus moisten the lime that has been pulverized and cause it to cake or assume a putty form when stored. By the addition of the steam a less .quantity of water can .be used, and thereby all liability of-the pulverized lime becoming vdampened is removed; besides the steam greatly hastens the process. This surplus moisture of any particles overmoist is driven off by the heating of the lime itself in slaking, whereas other particles needing moisture will absorb'the steam and the entire mass will become converted into a perfect hydrate. The continuous supply of steam into the cylinder will aid in the exclusion of airfrom the interior of the cylinder.

Itis important that as 'the lime becomes pulverized and reaches the hydrated state it should'be removed as rapidly as possible in order to avoid again absorbing moisture, which would tend to make it, cake or get lumpy when stored, and in order to prevent this the sprayed mass is moved slowly until the tine particles have been separated by sifting. Then the line particles are caused to move more rapidly to a barrel or receptacle in which they are to be packed.

Having thus fully des( ribed `my invention,

IOO

what I claim as new, and desire to secure by Letters Patent, is- L l. The process of hydratinglime consisting ot' taking a given quantity of quicklime1 tumbling, wetting and simultaneously therewith sifting same to immediately remove the hydrated particles and subjecting the remaining unhyclrated particles to the action of steam and continuing the tumbling and sifting to complete the hydration of said remaining particles.

2. The process of hydrating lime consisting oi' Weighing out a given quantity of quicli- 

